Gore belatedly gets the key message on emissions

Citing the US bill of rights, Al Gore stated during the recent Live Earth concerts: "We should demand that the US join an international [climate] treaty within the next two years that cuts global warming pollution by 90% in developed countries and by more than 50% worldwide in time for the next generation to inherit a healthy Earth."

At last, Gore says what is needed: contraction and convergence (C&C). This is the concept that came from the Global Commons Institute, based in the UK, which I set up in the early 1990s. It says that dangerous rates of climate change can be avoided only by countries agreeing to work together to safely limit the concentration of greenhouse gases in the atmosphere, and agreeing that emissions entitlements converge at a level that is equal, per capita, for all countries under that limit.

As we advance into worsening climate insecurity, C&C is becoming the most widely cited and advocated model needed to avoid climate catastrophe and worsening poverty.

But why didn't Gore, when he was US vice-president, back C&C at the 1997 UN climate negotiations in Kyoto? He claims to have known the seriousness of climate change since the 1980s. When he became vice-president, he knew that the US Senate required all countries to be in the treaty for it to be effective - either reducing or limiting their emissions, and internationally trading their entitlements.

In Kyoto, the US delegation said C&C was the sort of deal needed. But where was Gore? He arrived in the second week intending to persuade the European governments that they had to relax their emissions control by half, which they did. He then inexplicably went home early and missed the key exchanges. India, China and the Africa group all responded to C&C before, during and after Kyoto, saying they would have accepted C&C because it addressed poverty and climate change constitutionally in the same mechanism.

When C&C has been raised with Gore since then, he has said he doesn't buy it. But this is odd because he now appears to be selling it, and, by citing the bill of rights, he helps improve the odds further for C&C.

Beyond this, Gore recently got a job with the UK government to advise Britain on climate change awareness, communications and education. This puts him in a perfect position to challenge the government's new draft climate bill, which demands a mere 60% cut in UK emissions by 2050.

Parliament's environmental audit committee last week heavily criticised the government's climate bill. Encouragingly, however, the department for the environment is now led by Hilary Benn, who in the past has advocated C&C. And it has recruited the former chair of the Intergovernmental Panel on Climate Change, Bob Watson, as scientific adviser. Watson made C&C fundamental when advising the World Bank on dealing with climate and achieving the millennium goals.

The future is C&C.

· Aubrey Meyer is director of the Global Commons institute

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